[TheForge] Chip forge

[Jerry Frost]

There's been some discussion about "chip" size and material. The pictures 
I've seen of commercial chip forges have just that, chips. They look like 
gravel.

Packing is just what you don't want; you want a fairly unrestricted flame 
flow through the chips. Comments from people who have used chip forges say 
it can be hard to push small or delicate work into the chips. I think this 
is what lead to the discussion of making or buying spheres. I figured I'd 
use a shovel to cover delicate work but there might be damage pulling it 
out. I don't know.

I've given a couple shapes some thought:

Spheres will make for the least restriction in flame flow but provides the 
least surface area/volume ratio of any shape so heat transfer in and out 
will be minimum. Making spheres will I think be the most hassle as well.

Gravel like chips will be pretty easy to produce and having a high surface 
area/volume ratio will provide good heat transfer. Like I say making chips 
should be pretty straight foreward. Choose the refractory of your choice, 
ram, roll or cast it to the desired thickness, say 1/2". Let it dry, set, 
etc. and break it up till it passes a 1/2" seive. Lastly fire them like 
ceramic, using your chip forge of course. <grin>

Two minor (maybe) drawbacks being:

        1) Uniform gradation. The chips need to be pretty close to the same 
size to avoid packing so you'll end up with waste making them by the above 
method. Depending on the refractory you may or may not be able to 
reconstitute it with water and repeat the process.

        2) Keying. Keying means they'll lock together because of their 
irregular broken shapes and may cause damage pushing work in and pulling it 
out. Smoothing them a little after you break up the refractory will help but 
not eliminate the (maybe) problem. You also wouldn't want to smooth them too 
much or you lose surface/volume ratio.

As usual there's a compromise, or at least I think so. Here's the idea I'm 
going to try baring somebody else coming up with a good workable method, 
source, etc. I'll use a high temp rammable refractory and hammer it to a 
sheet 1/2" thick and then cut it into 1/2" cubes. While it's still plastic 
I'll gently roll the corners so they're not sharp. Hopefully this'll make 
"chips" with a good compromise between free flame flow and good 
surface/volume.

Here's an idea for making spheres. If you use the above method to make 3/8" 
cubes and roll them between boards 1/2" apart you will end up with spheres 
close to 1/2" dia. How well a refractory will stand up to being rolled from 
cubes to spheres will depend on how plastic the refractory is. If it works 
you'll be able to roll a lot of spheres at the same time.

Another variation on the above process is to roll "ropes" of the desired 
dia. and cut them to length. (I' ve been saying 1/2" but I just picked it 
arbitrarilly and another size may be better. I don't know)

Frosty
-------------------------------
If it ain't forged
it ain't real.
Wrought iron is.
The FrostWorks

Meadow Lakes, AK.

http://www.artmetalradio.com/

From: "Dan Brewer" <danqualman at gmail.com>


>
>
> __I seen discussion about the forge but no one has mentioned the size of 
> the
> balls.  Do they need to be balls or irregular pieces that pack similar to
> coal/coke.
> Dan in Auburn